Meta-analyses of treatment standards for pancreatic cancer

Plasma Metabolomics Predicts Chemotherapy Response in Advanced Pancreatic Cancer

Pancreatic cancer (PC) is one of the deadliest cancers. Developing biomarkers for chemotherapeutic response prediction is crucial for improving the dismal prognosis of advanced-PC patients (pts). To evaluate the potential of plasma metabolites as predictors of the response to chemotherapy for PC patients, we analyzed plasma metabolites using high-performance liquid chromatography-mass spectrometry from 31 cachectic, advanced-PC subjects enrolled into the PANCAX-1 (NCT02400398) prospective trial to receive a jejunal tube peptide-based diet for 12 weeks and who were planned for palliative chemotherapy. Overall, there were statistically significant differences in the levels of intermediates of multiple metabolic pathways in pts with a partial response (PR)/stable disease (SD) vs. progressive disease (PD) to chemotherapy. When stratified by the chemotherapy regimen, PD after 5-fluorouracil-based chemotherapy (e.g., FOLFIRINOX) was associated with decreased levels of amino acids (AAs). For gemcitabine-based chemotherapy (e.g., gemcitabine/nab-paclitaxel), PD was associated with increased levels of intermediates of glycolysis, the TCA cycle, nucleoside synthesis, and bile acid metabolism. These results demonstrate the feasibility of plasma metabolomics in a prospective cohort of advanced-PC patients for assessing the effect of enteral feeding as their primary source of nutrition. Metabolic signatures unique to FOLFIRINOX or gemcitabine/nab-paclitaxel may be predictive of a patient's response and warrant further study.

Malignancy risk factors and prognostic variables of pancreatic mucinous cystic neoplasms in Chinese patients

BACKGROUND

Pancreatic mucinous cystic neoplasms (MCNs) represent one of the precursor lesions of pancreatic ductal adenocarcinoma, and their detection has been facilitated by advances in preoperative imaging. Due primarily to the rarity of MCNs, however, there is limited knowledge regarding the prognostic variables and high-risk factors for malignant transformation. A more comprehensive and nuanced approach is necessary to fill this gap and provide a basis for improved treatment decisions and patient outcomes.

AIM

To investigate the high-risk factors associated with malignant MCNs and to explore the prognostic factors of MCN with associated invasive carcinoma (MCN-AIC).

METHODS

All cases of resected MCNs from a single high-volume institution between January 2012 and January 2022 were retrospectively reviewed. Only cases with ovarian-type stroma verified by progesterone receptor staining were included. Preoperative features, histological findings and postoperative course were documented. Multivariate logistic regression was employed to investigate variables related to malignancy. Survival analysis was performed using the Kaplan-Meier curve, and the prognostic factors were assessed to evaluate the postoperative course of patients with MCN-AIC.

RESULTS

Among the 48 patients, 36 had benign MCNs, and 12 had malignant MCNs (1 high-grade atypical hyperplasia and 11 MCN-AIC). Age, tumour size, presence of solid components or mural nodules and pancreatic duct dilatation were identified as independent risk factors associated with malignancy. The follow-up period ranged from 12 mo to 120 mo, with a median overall survival of 58.2 mo. Only three patients with MCN-AIC died, and the 5-year survival rate was 70.1%. All 11 cases of MCN-AIC were stage I, and extracapsular invasion was identified as a prognostic factor for poorer outcomes.

CONCLUSION

The risk factors independently associated with malignant transformation of MCNs included age, tumour size, presence of solid components or mural nodules, and pancreatic duct dilatation. Our study also revealed that encapsulated invasion was a favourable prognostic factor in MCN-AIC patients.

Combination L-Glutamine with Gemcitabine and Nab-Paclitaxel in Treatment-Naïve Advanced Pancreatic Cancer: The Phase I GlutaPanc Study Protocol

Advanced pancreatic cancer is underscored by progressive therapeutic resistance and a dismal 5-year survival rate of 3%. Preclinical data demonstrated glutamine supplementation, not deprivation, elicited antitumor effects against pancreatic ductal adenocarcinoma (PDAC) alone and in combination with gemcitabine in a dose-dependent manner. The GlutaPanc phase I trial is a single-arm, open-label clinical trial investigating the safety of combination L-glutamine, gemcitabine, and nab-paclitaxel in subjects (n = 16) with untreated, locally advanced unresectable or metastatic pancreatic cancer. Following a 7-day lead-in phase with L-glutamine, the dose-finding phase via Bayesian design begins with treatment cycles lasting 28 days until disease progression, intolerance, or withdrawal. The primary objective is to establish the recommended phase II dose (RP2D) of combination L-glutamine, gemcitabine, and nab-paclitaxel. Secondary objectives include safety of the combination across all dose levels and preliminary evidence of antitumor activity. Exploratory objectives include evaluating changes in plasma metabolites across multiple time points and changes in the stool microbiome pre and post L-glutamine supplementation. If this phase I clinical trial demonstrates the feasibility of L-glutamine in combination with nab-paclitaxel and gemcitabine, we would advance the development of this combination as a first-line systemic option in subjects with metastatic pancreatic cancer, a high-risk subgroup desperately in need of additional therapies.

Gut microbiome and pancreatic cancer cachexia: An evolving relationship

Nearly 80% of patients with pancreatic ductal adenocarcinoma (PDAC) develop cachexia along their disease course. Cachexia is characterized by progressive weight loss, muscle wasting, and systemic inflammation and has been linked to poorer outcomes and impairments in quality of life. Management of PDAC cachexia has historically involved a multidisciplinary effort comprised of nutritional support, pancreatic enzyme replacement therapy, and/or pharmacologic interventions. Despite current interventions to mitigate PDAC cachexia, a significant proportion of patients continue to die from complications associated with cachexia underscoring the need for novel insights and treatments for this syndrome. We highlight the feasibility and effectiveness of a recent enteral feeding prospective trial at our institution to improve cachexia outcomes in patients with advanced PDAC. Additionally, we were among the first to characterize the stool microbiome composition in patients with advanced PDAC receiving enteral feeding for the treatment of cachexia. Novel insights into the relationship between enteral nutritional support, cachexia, and the gut microbiome are presented. These promising results are discussed in the context of a potential ability to modulate the stool microbiome as a new interventional strategy to mitigate PDAC cachexia.

The natural sulfoglycolipid derivative SQAP improves the therapeutic efficacy of tissue factor-targeted radioimmunotherapy in the stroma-rich pancreatic cancer model BxPC-3

•

SQAP enhanced tumor uptake and the therapeutic efficacy of radiolabeled anti-tissue factor antibody 1849.

•

SQAP allows for a reduction of the dose of the therapeutic agent ⁹⁰Y-labeled 1849 to half.

•

SQAP did not affect hematologic parameters, or gastrointestinal and respiratory systems in mice.

•

⁹⁰Y-labeled 1849 with SQAP potentially increases exposure of tumors to radiation.

α-Sulfoquinovosylacyl-1,3-propanediol (SQAP) is a semi-synthetic derivative of natural sulfoglycolipid that sensitizes tumors to external-beam radiotherapy. How SQAP affects internal radiotherapy, however, is not known. Here, we investigated the effects of SQAP for radioimmunotherapy (RIT) targeting tissue factor (TF) in a stroma-rich refractory pancreatic cancer mouse model, BxPC-3. A low dose of SQAP (2 mg/kg) increased tumor uptake of the ¹¹¹In-labeled anti-TF antibody 1849, indicating increased tumor perfusion. The addition of SQAP enhanced the growth-inhibitory effect of ⁹⁰Y-labeled 1849 without leading to severe body weight changes, allowing for the dose of ⁹⁰Y-labeled 1849 to be reduced to half that when used alone. Histologic analysis revealed few necrotic and apoptotic cells, but Ki-67–positive proliferating cells and increased vascular formation were detected. These results suggest that the addition of a low dose of SQAP may improve the therapeutic efficacy of TF-targeted RIT by increasing tumor perfusion, even for stroma-rich refractory pancreatic cancer.

Proof of Concept Study for Increasing Tenascin-C-Targeted Drug Delivery to Tumors Previously Subjected to Therapy: X-Irradiation Increases Tumor Uptake

Simple Summary

We hypothesized that an agent recognizing a specific factor, which is involved in tissue injury repair, could achieve the goal of delivering an additional antitumor agent to tumors during tissue repair after initial anticancer therapy. To demonstrate our concept, the present study employed tenascin-C (TNC) as a target molecule and radiation as initial therapy. Increased TNC expression was observed in tumors after radiation exposure in a pancreatic cancer mouse model. Of our three anti-TNC antibodies, the antibody 3–6 showed statistically significant higher tumor uptake compared with non-irradiated tumors in the by biodistribution and single-photon emission computed tomography with computed tomography studies. This finding strongly supports our concept. Our proposed therapeutic strategy could result in better outcomes for patients with treatment-refractory cancer.

Abstract

In treatment-refractory cancers, tumor tissues damaged by therapy initiate the repair response; therefore, tumor tissues must be exposed to an additional burden before successful repair. We hypothesized that an agent recognizing a molecule that responds to anticancer treatment-induced tissue injury could deliver an additional antitumor agent including a radionuclide to damaged cancer tissues during repair. We selected the extracellular matrix glycoprotein tenascin-C (TNC) as such a molecule, and three antibodies recognizing human and murine TNC were employed to evaluate X-irradiation-induced changes in TNC uptake by subcutaneous tumors. TNC expression was assessed by immunohistochemical staining of BxPC-3 tumors treated with or without X-irradiation (30 Gy) for 7 days. Antibodies against TNC (3–6, 12–2–7, TDEAR) and a control antibody were radiolabeled with ¹¹¹In and injected into nude mice having BxPC-3 tumors 7 days after X-irradiation, and temporal uptake was monitored for an additional 4 days by biodistribution and single-photon emission computed tomography with computed tomography (SPECT/CT) studies. Intratumoral distribution was analyzed by autoradiography. The immunohistochemical signal for TNC expression was faint in nontreated tumors but increased and expanded with time until day 7 after X-irradiation. Biodistribution studies revealed increased tumor uptake of all three ¹¹¹In-labeled antibodies and the control antibody. However, a statistically significant increase in uptake was evident only for ¹¹¹In-labeled 3–6 (35% injected dose (ID)/g for 30 Gy vs. 15% ID/g for 0 Gy at day 1, p < 0.01), whereas limited changes in ¹¹¹In-labeled TDEAR2, 12–2–27, and control antibody were observed (several % ID/g for 0 and 30 Gy). Serial SPECT/CT imaging with ¹¹¹In-labeled 3–6 or control antibody provided consistent results. Autoradiography revealed noticeably stronger signals in irradiated tumors injected with ¹¹¹In-labeled 3–6 compared with each of the nonirradiated tumors and the control antibody. The signals were observed in TNC-expressing stroma. Markedly increased uptake of ¹¹¹In-labeled 3–6 in irradiated tumors supports our concept that an agent, such as an antibody, that recognizes a molecule involved in tissue injury repair, such as TNC, could enhance drug delivery to tumor tissues that have undergone therapy. The combination of antibody 3–6 coupled to a tumoricidal drug and conventional therapy has the potential to achieve better outcomes for patients with refractory cancer.

Impact of progressive resistance training on CT quantified muscle and adipose tissue compartments in pancreatic cancer patients

Objectives

Loss of body weight is often seen in pancreatic cancer and also predicts poor prognosis. Thus, maintaining muscle mass is an essential treatment goal. The primary aim was to investigate whether progressive resistance training impacts muscle and adipose tissue compartments. Furthermore, the effect of body composition on overall survival (OS) was investigated.

Methods

In the randomized SUPPORT-study, 65 patients were assigned to 6-month resistance training (2x/week) or a usual care control group. As secondary endpoint, muscle strength of the upper and lower extremities was assessed before and after the intervention period. Routine CT scans were assessed on lumbar L3/4 level for quantification of total-fat-area, visceral-fat-area, subcutaneous-fat-area, intramuscular-fat-area, visceral-to-subcutaneous fat ratio (VFR), muscle-area (MA), muscle-density and skeletal-muscle-index (SMI). OS data were retrieved.

Results

Of 65 patients, 53 had suitable CT scans at baseline and 28 completed the intervention period with suitable CT scans. There were no significant effects observed of resistance training on body composition (p>0.05; effect sizes ω²_p <0.02). Significant moderate to high correlations were found between MA and muscle strength parameters (r = 0.57–0.85; p<0.001). High VFR at baseline was a predictor of poor OS (VFR≥1.3 vs. <1.3; median OS 14.6 vs. 45.3 months; p = 0.012). Loss of muscle mass was also a predictor of poor OS (loss vs. gain of SMI; median OS 24.6 vs. 50.8 months; p = 0.049).

Conclusion

There is anabolic potential in patients with resectable pancreatic cancer. A progressive resistance training may help patients to maintain their muscle mass and avoid muscle depletion. CT-quantified muscle mass at the level of L3/4 showed a good correlation to muscle strength. Therefore, maintaining muscle mass and muscle strength through structured resistance training could help patients to maintain their physical functioning. A high VFR at baseline and a high loss of muscle mass are predictors of poor OS. Registered on ClinicalTrials.gov (NCT01977066).

Radiation as a Single-Modality Treatment in Localized Pancreatic Cancer

OBJECTIVES

Locally advanced pancreatic cancer (LAPC) is managed with multimodality therapy. We aim to evaluate the outcome of single-modality radiation therapy for LAPC.

METHODS

Locally advanced pancreatic cancer patients were identified between 2004 and 2013 using the National Cancer Database excluding patients who received chemotherapy or surgery.

RESULTS

A total of 6590 patients were included. The mean age was 73.5 (range, 28-90) years, 83.2% were white, and 54.4% were female. Tumors of 4 cm or greater (>T3 stage) accounted for 52.7%. The median radiation dose was 39.6 Gy. Stereotactic body radiation (SBRT) delivered to 64 patients and external-beam/intensity modulated radiotherapy in 416 patients. Radiation therapy was associated with improved overall survival (OS) compared with no treatment in univariate and multivariable analyses. The medians OS for patients who received SBRT, external-beam/intensity modulated radiotherapy, or no radiation were 8.6, 6.7, and 3.4 months, respectively (P < 0.001). There is a significant difference in 12-month OS for the SBRT cohort (31.9%; 95% confidence interval [CI], 20.9%-43.5%) compared with patients who received no radiation (15.1%; 95% CI, 14.2%-16.0%), and on multivariable analysis (hazard ratio, 0.50; 95% CI, 0.38-0.65; P < 0.001).

CONCLUSIONS

The current study suggests potential benefit for radiation therapy alone in comparison with no treatment in LAPC.

Quality of Life, Fatigue, and Sleep Problems in Pancreatic Cancer Patients—A Randomized Trial on the Effects of Exercise

BACKGROUND

Improving quality of life (QoL) is an important treatment goal in pancreatic cancer patients. Although the beneficial effects of exercise on QoL are well understood, few studies have investigated more aggressive cancers such as pancreatic cancer.

METHODS

Within a randomized trial, we assessed the efficacy of 6-month resistance training on physical functioning (primary outcome) and further QoL-related outcomes. 65 pancreatic cancer patients were assigned to home-based training, supervised training, or a usual care control group. Analysis-of-covariance models on changes from baseline to 6 and 3 months were ap- plied.

RESULTS

47 patients completed the intervention period. After 6 months, no effects of resistance training were observed. However, after 3 months, explorative analyses showed significant between-group mean differences (MD) in favor for resistance training for physical functioning (pooled group: MD=11.0; p=0.016; effect size[ES]=0.31), as well as for global QoL (MD=12.1; p=0.016; effect size=0.56), and other outcomes, such as sleep problems and fatigue. Multiple imputation analyses yielded similar results. Home-based and supervised training performed similarly.

CONCLUSION

This first randomized resistance training trial in pancreatic cancer patients indicated clinically relevant improve- ments in QoL after 3 but not after 6 months. Given the severity of pancreatic cancer, exercise recommendations may already commence at surgery.

The impact of immunotherapy on the survival of pancreatic adenocarcinoma patients who do not receive definitive surgery of the tumor

Background and Purpose

Immunotherapy has shown great efficacy in many cancers, but its role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. The objective of this study was to investigate the impact of immunotherapy on the overall survival of PDAC patients who did not receive definitive surgery of the pancreatic primary tumor site using the National Cancer Database (NCDB).

Materials and Methods

Patients with pancreatic adenocarcinoma who did not receive surgery were identified from NCDB. Cox proportional hazard models were employed to assess the impact of immunotherapy on survival after adjusting for age at diagnosis, race, sex, place of living, income, education, treatment facility type, insurance status, year of diagnosis, and treatment types such as chemotherapy and radiation therapy.

Results

Of 263,886 patients who were analyzed, 911 (0.35%) received immunotherapy. Among patients who received chemotherapy (101,546), and chemoradiation (30,226) therapy, 555/101,546 (0.55%) received chemotherapy plus immunotherapy, and 299/3,022 (9.9%) received chemoradiation plus immunotherapy. In a multivariable analysis adjusted for the factors mentioned above, immunotherapy was associated with significantly improved OS (HR: 0.866 (0.800–0.937); P < 0.001) compared to no immunotherapy. Chemotherapy plus immunotherapy was significantly associated with improved OS (HR: 0.848 (0.766–0.938); P < 0.001) compared to chemotherapy without immunotherapy. Further, chemoradiation plus immunotherapy was associated with significantly improved OS (HR: 0.813 (0.707–0.936); P < 0.001) compared to chemoradiation alone.

Conclusion

In this study, the addition of immunotherapy to chemotherapy and chemoradiation therapy was associated with significantly improved OS in PDAC patients without definitive surgery. The study warrants future clinical trials of immunotherapy in PDAC.

The Vacuolar H+ ATPase α3 Subunit Negatively Regulates Migration and Invasion of Human Pancreatic Ductal Adenocarcinoma Cells

Increased metabolic acid production and upregulation of net acid extrusion render pH homeostasis profoundly dysregulated in many cancers. Plasma membrane activity of vacuolar H+ ATPases (V-ATPases) has been implicated in acid extrusion and invasiveness of some cancers, yet often on the basis of unspecific inhibitors. Serving as a membrane anchor directing V-ATPase localization, the a subunit of the V0 domain of the V-ATPase (ATP6V0a1-4) is particularly interesting in this regard. Here, we map the regulation and roles of ATP6V0a3 in migration, invasion, and growth in pancreatic ductal adenocarcinoma (PDAC) cells. a3 mRNA and protein levels were upregulated in PDAC cell lines compared to non-cancer pancreatic epithelial cells. Under control conditions, a3 localization was mainly endo-/lysosomal, and its knockdown had no detectable effect on pHi regulation after acid loading. V-ATPase inhibition, but not a3 knockdown, increased HIF-1 expression and decreased proliferation and autophagic flux under both starved and non-starved conditions, and spheroid growth of PDAC cells was also unaffected by a3 knockdown. Strikingly, a3 knockdown increased migration and transwell invasion of Panc-1 and BxPC-3 PDAC cells, and increased gelatin degradation in BxPC-3 cells yet decreased it in Panc-1 cells. We conclude that in these PDAC cells, a3 is upregulated and negatively regulates migration and invasion, likely in part via effects on extracellular matrix degradation.

Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors

Multidetector computed tomography (MDCT) is a widely used cross-sectional imaging modality for initial evaluation of patients with suspected pancreatic ductal adenocarcinoma (PDAC). However, diagnosis of PDAC can be challenging due to numerous pitfalls associated with image acquisition and interpretation, including technical factors, imaging features, and cognitive errors. Accurate diagnosis requires familiarity with these pitfalls, as these can be minimized using systematic strategies. Suboptimal acquisition protocols and other technical errors such as motion artifacts and incomplete anatomical coverage increase the risk of misdiagnosis. Interpretation of images can be challenging due to intrinsic tumor features (including small and isoenhancing masses, exophytic masses, subtle pancreatic duct irregularities, and diffuse tumor infiltration), presence of coexisting pathology (including chronic pancreatitis and intraductal papillary mucinous neoplasm), mimickers of PDAC (including focal fatty infiltration and focal pancreatitis), distracting findings, and satisfaction of search. Awareness of pitfalls associated with the diagnosis of PDAC along with the strategies to avoid them will help radiologists to minimize technical and interpretation errors. Cognizance and mitigation of these errors can lead to earlier PDAC diagnosis and ultimately improve patient prognosis.

Adjuvant treatment for resected pancreatic adenocarcinoma: A systematic review and network meta-analysis

Adjuvant chemotherapy has significantly improved outcomes following surgical resection for pancreatic adenocarcinoma; however, the optimal adjuvant strategy remains unclear. This systematic review and network meta-analysis was conducted to provide indirect comparative evidence across adjuvant chemotherapies. Electronic searches of EMBASE, MEDLINE, Cochrane and ASCO databases were conducted to identify eligible randomized controlled trials (RCT). Direct pairwise meta-analysis was conducted for disease-free survival (DFS), overall-survival (OS) and adverse events (AE). Network meta-analysis of DFS and OS was conducted to evaluate indirect comparisons. Ten publications of eleven RCT met eligibility criteria. Indirect DFS comparison demonstrated superiority of mFOLFIRINOX versus gemcitabine-capecitabine, gemcitabine-erlotinib and gemcitabine-nab-paclitaxel. S-1 demonstrated a DFS benefit versus gemcitabine-capecitabine, gemcitabine-erlotinib, gemcitabine-nab-paclitaxel. OS benefits were demonstrated for mFOLFIRINOX verus gemcitabine-erlotinib and for S-1 versus gemcitabine-based combination with erlotinib, capecitabine and nab-paclitaxel. In conclusion, mFOLFIRINOX is the preferred approach for adjuvant therapy. For mFOLFIRINOX-ineligible patients no additional benefit is seen with gemcitabine-nab-paclitaxel.

Phase I/II Study: Experience with the Late Onset of Acute Pancreatitis after the Start of Chemotherapy with Gemcitabine Plus nab-Paclitaxel for Metastatic Pancreatic Cancer

Gemcitabine plus nab-paclitaxel is the current standard chemotherapy for patients with metastatic pancreatic cancer. We conducted a phase I/II study in Japan, in which high response rates and manageable toxicity were observed. In this study, two patients were reported as experiencing pancreatitis due to chemotherapy. In general, pancreatitis is sometimes observed when the tumor involves the pancreatic duct, and the onset is observed before the diagnosis or at the initial stage. The onset of pancreatitis in these cases was unique and observed after the start of chemotherapy. Pancreatitis may be induced by the alleviation of stenosis of the pancreatic duct associated with tumor shrinkage.

Comparison of Radiosensitization by HDAC Inhibitors CUDC-101 and SAHA in Pancreatic Cancer Cells

Pancreatic cancer has a poor prognosis. New treatment options are urgently required to improve patient outcomes. One promising new class of anticancer drugs are synthetic histone deacetylase inhibitors (HDACi) which modulate chromatin structure and gene expression by blocking histone deacetylation. In this study, we aimed at comparing the in vitro capacities of the HDACi SAHA and CUDC-101 to increase radiosensitivity of human pancreatic tumor cell lines. Therefore, three pancreatic cancer cell lines (Su.86.86, MIA Paca-2, T3M-4) were treated with SAHA (1.5–5 µM) or CUDC-101 (0.25–3 µM) and after 24 h irradiated. Cell proliferation, clonogenic survival and apoptosis was determined. Additionally, cell lysates were investigated for the expression of apoptosis-related proteins. CUDC-101 and SAHA increased the radiation sensitivity of pancreatic tumor cell lines in a dose-dependent manner. This was evidenced by cell proliferation and clonogenic survival. Furthermore, enhanced radiation sensitivity after CUDC-101 or SAHA treatment was confirmed for Su.86.86 and T3M-4 cells in a 3-D microtissue approach. Increased amounts of subG1 cells and diminished full length PARP-1 suggest increased radiation-induced apoptosis after SAHA or CUDC-101 treatment. The comparison of both inhibitors in these assays manifested CUDC-101 as more potent radiosensitizer than SAHA. In line, western blot quantification of the apoptosis-inhibitory proteins XIAP and survivin showed a stronger down-regulation in response to CUDC-101 treatment than after SAHA application. These proteins may contribute to the synergy between HDAC inhibition and radiation response. In conclusion, these preclinical results suggest that treatment with the HDAC inhibitors CUDC-101 or SAHA can enhance radiation-induced cytotoxicity in human pancreatic cells. However, comparison of both inhibitors identified the multi target inhibitor CUDC-101 as more potent radiosensitizer than the HDAC inhibitor SAHA.

Role of adjuvant therapy in resected stage IA subcentimeter (T1a/T1b) pancreatic cancer

BACKGROUND

The standard of care for patients with resected stage I to stage III pancreatic ductal adenocarcinoma (PDAC) is adjuvant gemcitabine-based chemotherapy. The role of adjuvant treatment in patients with subcentimeter, stage IA PDAC is unknown. The current study evaluated the effect of adjuvant treatment on survival outcomes among patients with American Joint Committee on Cancer/International Union Against Cancer stage IA (T1N0) resected PDAC using the National Cancer Data Base (NCDB).

METHODS

A retrospective review of the NCDB was conducted for patients diagnosed with T1 (tumor limited to the pancreas and measuring ≤2 cm in greatest dimension), lymph node-negative (N0), resected PDAC between 2004 and 2013. Patient demographics, histology, adjuvant treatment, and survival trends were examined. Kaplan-Meier analysis and log-rank tests were performed to determine the unadjusted association between overall survival (OS), tumor size, and treatment.

RESULTS

A total of 876 patients met the inclusion criteria. The patients had a mean age of 66.2 years (range, 32-90 years); approximately 83.3% were white (730 patients) and 53.1% were female (465 patients). Approximately 45.9% of the patients had moderately differentiated tumor histology (402 patients); 70.0% (613 patients) had tumors measuring 1 to 2 cm (T1c) and 30.0% (263 patients) had tumors measuring <1 cm (T1a/T1b). Approximately 94.2% of patients had negative surgical margins (815 patients) and 46.9% (410 patients) received adjuvant therapy. The median OS was significantly different for patients who received adjuvant therapy compared with patients who did not (70.7 months vs 46.9 months; P = .0001). For patients with tumors measuring <1 cm, survival was not found to be significantly different between patients who received adjuvant treatment compared with those who did not (not reached vs 85.3 months; P = .54). In the multivariable analysis, none of the covariates (treatment group, Charlson-Deyo Score, age, insurance, and facility status) demonstrated significant differences for patients with tumors measuring <1 cm.

CONCLUSIONS

The current study is the first to demonstrate no survival benefit for adjuvant therapy in patients with resected subcentimeter PDAC.

Efficacy Evaluation of Combination Treatment Using Gemcitabine and Radioimmunotherapy with 90Y-Labeled Fully Human Anti-CD147 Monoclonal Antibody 059-053 in a BxPC-3 Xenograft Mouse Model of Refractory Pancreatic Cancer

The poor prognosis of pancreatic cancer requires the development of more effective therapy. CD147 expresses in pancreatic cancer with high incidence and has a crucial role in invasion and metastasis. We developed a fully human monoclonal antibody (059-053) with high affinity for CD147. Here we evaluated the efficacy of combined treatment using radioimmunotherapy (RIT) with ⁹⁰Y-labeled 059-053 and gemcitabine in a BxPC-3 xenograft mouse model. Expression of CD147 and matrix metalloproteinase-2 (MMP2) in BxPC-3 tumors was evaluated. In vitro and in vivo properties of 059-053 were evaluated using ¹¹¹In-labeled 059-053 and a pancreatic cancer model BxPC-3. Tumor volume and body weight were periodically measured in mice receiving gemcitabine, RIT, and both RIT and gemcitabine (one cycle and two cycles). High expression of CD147 and MMP2 was observed in BxPC-3 tumors and suppressed by 059-053 injection. Radiolabeled 059-053 bound specifically to BxPC-3 cells and accumulated highly in BxPC-3 tumors but low in major organs. Combined treatment using RIT with gemcitabine (one cycle) significantly suppressed tumor growth and prolonged survival with tolerable toxicity. The two-cycle regimen had the highest anti-tumor effect, but was not tolerable. Combined treatment with ⁹⁰Y-labeled 059-053 and gemcitabine is a promising therapeutic option for pancreatic cancer.

The BET inhibitor I-BET762 inhibits pancreatic ductal adenocarcinoma cell proliferation and enhances the therapeutic effect of gemcitabine

As one of the most fatal malignancies, pancreatic ductal adenocarcinoma (PDAC) has significant resistance to the currently available treatment approaches. Gemcitabine, the standard chemotherapeutic agent for locally advanced and metastatic PDAC, has limited efficacy, which is attributed to innate/acquired resistance and the activation of prosurvival pathways. Here, we investigated the in vitro efficacy of I-BET762, an inhibitor of the bromodomain and extraterminal (BET) family of proteins, in treating PDAC cell lines alone and in combination with gemcitabine (GEM). The effect of these two agents was also examined in xenograft PDAC tumors in mice. We found that I-BET762 induced cell cycle arrest in the G0/G1 phase and cell death and suppressed cell proliferation and metastatic stem cell factors in PDAC cells. In addition, the BH3-only protein Bim, which is related to chemotherapy resistance, was upregulated by I-BET762, which increased the cell death triggered by GEM in PDAC cells. Moreover, GEM and I-BET762 exerted a synergistic effect on cytotoxicity both in vitro and in vivo. Furthermore, Bim is necessary for I-BET762 activity and modulates the synergistic effect of GEM and I-BET762 in PDAC. In conclusion, we investigated the effect of I-BET762 on PDAC and suggest an innovative strategy for PDAC treatment.

The emerging role of stereotactic radiotherapy in gastrointestinal malignancies: a review of the literature and analysis from the Irish perspective

Primary and secondary malignancies of the liver and pancreas result in significant morbidity and mortality, with increasing incidence and increasing demands on health services worldwide. Surgery is the only curative single modality of treatment and remains the gold standard. Unfortunately, up to 80% of the patients present with unresectable disease, and so, alternative efficacious local and systemic treatments are needed. Technologic advances in radiotherapy over recent decades have meant that precision high-dose treatment with stereotactic body radiotherapy (SBRT) has emerged as a viable cost-effective outpatient-based treatment in the management of these difficult to treat abdominal malignancies. This article reviews the current indications for SBRT in these settings, comparing it with other treatments including surgery, chemotherapy, radiofrequency ablation, and trans-arterial chemoembolisation. We also review the current use of abdominal SBRT and future projections in the Irish healthcare setting.

The synthetic diazonamide DZ-2384 has distinct effects on microtubule curvature and dynamics without neurotoxicity

Microtubule-targeting agents (MTAs) are widely used anticancer agents, but toxicities such as neuropathy limit their clinical use. MTAs bind to and alter the stability of microtubules, causing cell death in mitosis. We describe DZ-2384, a preclinical compound that exhibits potent antitumor activity in models of multiple cancer types. It has an unusually high safety margin and lacks neurotoxicity in rats at effective plasma concentrations. DZ-2384 binds the vinca domain of tubulin in a distinct way, imparting structurally and functionally different effects on microtubule dynamics compared to other vinca-binding compounds. X-ray crystallography and electron microscopy studies demonstrate that DZ-2384 causes straightening of curved protofilaments, an effect proposed to favor polymerization of tubulin. Both DZ-2384 and the vinca alkaloid vinorelbine inhibit microtubule growth rate; however, DZ-2384 increases the rescue frequency and preserves the microtubule network in nonmitotic cells and in primary neurons. This differential modulation of tubulin results in a potent MTA therapeutic with enhanced safety.

Utilization and trends in palliative therapy for stage IV pancreatic adenocarcinoma patients: a U.S. population-based study

BACKGROUND

Pancreatic adenocarcinoma is an aggressive malignancy, with most patients diagnosed with advanced or metastatic disease. Palliative therapies comprise an important, but underutilized, aspect of care. This aim of this study was to characterize the trends, factors, and outcomes associated with utilization of palliative therapies.

METHODS

Patients with stage IV pancreatic adenocarcinoma from the 2003-2011 U.S. National Cancer Database were identified and stratified by receipt of palliative therapy. Linear regression, multivariable logistic regression, and survival analyses using multivariate proportional hazards models were performed.

RESULTS

Sixty-eight thousand and seventy-five patients with stage IV disease were identified, of which only 11,449 (16.8%) underwent designated palliative therapy. The majority received systemic chemotherapy (37.2%), followed by surgery (19.0%), pain management alone (15.3%), radiation (8.1%), referral alone (11.7%), or a combination thereof (8.7%). Utilization of palliative therapies increased from 12.9% in 2003 to 19.2% in 2011 (P<0.001). Patients were less likely to undergo palliation when older than 60 (OR 0.89, P<0.001), or of black or Hispanic race (OR 0.83, P<0.001; OR 0.80, P<0.001, respectively, vs. Caucasians). Presence of comorbidities increased the use of palliative therapy (OR 1.16 per comorbidity, P<0.001). Survival was improved in those receiving palliative systemic chemotherapy (HR 0.55, P<0.001) and palliative surgery (HR 0.94, P<0.001), although this may be due to selection bias.

CONCLUSIONS

Despite the continued dismal prognosis of pancreatic cancer, palliation of symptoms remains underutilized in this country, particularly in non-Caucasian, older patients. Increased awareness of palliative options may help increase its utilization.

Cardiorespiratory fitness and muscle strength in pancreatic cancer patients

PURPOSE

Cancer patients frequently experience reduced physical fitness due to the disease itself as well as treatment-related side effects. However, studies on physical fitness in pancreatic cancer patients are missing. Therefore, we assessed cardiorespiratory fitness and muscle strength of pancreatic cancer patients.

METHODS

We included 65 pancreatic cancer patients, mostly after surgical resection. Cardiorespiratory fitness was assessed using cardiopulmonary exercise testing (CPET) and 6-min walk test (6MWT). Hand-held dynamometry was used to evaluate isometric muscle strength. Physical fitness values were compared to reference values of a healthy population. Associations between sociodemographic and clinical variables with patients' physical fitness were analyzed using multiple regression models.

RESULTS

Cardiorespiratory fitness (VO₂peak, 20.5 ± 6.9 ml/min/kg) was significantly lower (-24%) compared to healthy reference values. In the 6MWT pancreatic cancer patients nearly reached predicted values (555 vs. 562 m). Maximal voluntary isometric contraction (MVIC) of the upper (-4.3%) and lower extremities (-13.8%) were significantly lower compared to reference values. Overall differences were larger in men than those in women. Participating in regular exercise in the year before diagnosis was associated with greater VO₂peak (p < .05) and MVIC of the knee extensors (p < .05).

CONCLUSIONS

Pancreatic cancer patients had significantly impaired physical fitness with regard to both cardiorespiratory function and isometric muscle strength, already in the early treatment phase (median 95 days after surgical resection). Our findings underline the need to investigate exercise training in pancreatic cancer patients to counteract the loss of physical fitness.

The Wnt/β-catenin signaling pathway mechanism for pancreatic cancer chemoresistance in a three-dimensional cancer microenvironment

β-catenin is a key protein that is encoded by the CTNNB1 gene in the Wnt signaling pathway. This study investigated the associations between β-catenin expression and implications for the efficacy of gemcitabine on pancreatic cancer cells in a three-dimensional (3-D) cancer microenvironment. For low β-catenin expression pancreatic carcinoma cells, the inhibition rates (IRs) for low, middle, and high doses of gemcitabine were 0.615 ± 0.079, 0.691 ± 0.093, and 0.765 ± 0.061, respectively. For the high β-catenin expression pancreatic carcinoma cells, the IRs for the same doses were 0.325 ± 0.072, 0.453 ± 0.075, and 0.537 ± 0.056, respectively. Additionally, the evaluation of β-catenin immunoreactivity in 31 pancreatic cancer patients revealed that the low β-catenin protein expression group had significantly longer overall survival (OS) and disease free survival (DFS) than the high β-catenin protein group (P < 0.05). Overall, β-catenin protein expression levels were significantly correlated to gemcitabine sensitivity in seven pancreatic carcinoma cell lines in the 3-D cancer microenvironment. These data suggest that large-scale clinical studies are warranted to assess the role of the Wnt/β-catenin signaling pathway on β-catenin protein expression and chemosensitivity to gemcitabine in pancreatic cancer.